Hygienic Coupling and Fitting Seal System

ABSTRACT

A seal system ( 10 ) includes a tail ( 14 ) having parallel, spaced, annular first and second surfaces ( 16, 18 ). The tail ( 14 ) further includes spaced, first and second peripheral edges ( 22, 28 ) extending between and adjoining the first and second surfaces ( 16, 18 ). An annular ring ( 40 ) integrally extends from a portion of the tail ( 14 ) from the first peripheral edge ( 22 ) towards but spaced from the second peripheral edge ( 28 ). The annular ring ( 40 ) and the portion of the tail ( 14 ) form a seal ( 54 ) that includes an exterior including the first peripheral edge ( 22 ). The exterior of the seal ( 54 ) has a thickness (D) parallel to a thickness (T) of the tail ( 14 ) between the first and second surfaces ( 16, 18 ). The thickness (D) of the seal ( 54 ) continuously increases and then continuously decreases from the first peripheral edge ( 22 ) towards the second peripheral edge ( 28 ). The exterior of the seal ( 54 ) is free of protrusions.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims benefit of U.S. Application No.61/021,272 filed on Jan. 15, 2008.

BACKGROUND OF THE INVENTION

The present invention relates to a seal system and, more particularly,to a hygienic coupling and fitting seal system for pharmaceutical,dairy, beverage, or other sanitary industries.

Various seals have been widely utilized in various industries. The sealsutilized in plants or factories processing pharmaceutical, beverage,dairy products, or the like should be taken apart for periodic cleaningand should be made of a material capable of withstanding the processing.However, “binding”, “rippling up”, and “intrusion” commonly occurred onconventional seals, including but not limited to flat gaskets, O-rings,and other industry standard gaskets, creating potential for loosing thesealing effect and for becoming a hygienic issue. For agitatorcouplings, conventional O-rings that are exposed and flush or slightlyprotrude do not always remain engaged and can actually loose the sealingeffect and fall out.

Thus, a need exists for a hygienic coupling and fitting seal system thatis easy to clean while providing reliable sealing effect.

BRIEF SUMMARY OF THE INVENTION

The present invention solves this need and other problems in the fieldof hygienic coupling and fitting seals by providing, in a preferredform, a seal system including a tail having an annular first surface andan annular second surface parallel to and spaced from the annular firstsurface in a first direction. The tail has a first thickness between theannular first and second surfaces in the first direction. The tailfurther includes first and second peripheral edges extending between andadjoining the annular first and second surfaces. The first and secondperipheral edges are spaced from each other in a second directionperpendicular to the first direction. A first annular ring integrallyextends from a portion of the tail for a first extent from the firstperipheral edge towards but spaced from the second peripheral edge ofthe tail. The first annular ring and the portion of the tail form aseal. The seal includes an exterior including the first peripheral edge.The exterior of the seal has a second thickness parallel to the firstthickness. The second thickness of the seal continuously increases andthen continuously decreases from the first peripheral edge towards thesecond peripheral edge of the tail. The exterior of the seal is free ofprotrusions.

In preferred forms, the first annular ring integrally extends from theannular first surface, and the exterior of the seal includes the annularsecond surface for the first extent from the first peripheral edgetowards but spaced from the second peripheral edge. The seal hasgenerally semicircular cross sections in a plane including the first andsecond directions. In alternate preferred forms, the first annular ringintegrally extends from the annular first and second surfaces, and theseal has generally circular cross sections in the plane including thefirst and second directions.

In a preferred form, a second annular ring integrally extends fromanother portion of the tail for a second extent from the secondperipheral edge towards but spaced from the first peripheral edge. Thesecond annular ring and the other portion of the tail form a sealelement. The seal element includes an exterior including the secondperipheral edge. The exterior of the seal element has a third thicknessparallel to the first thickness. The third thickness of the seal elementcontinuously increases and then continuously decreases from the secondperipheral edge towards the first peripheral edge. The exterior of theseal element is free of protrusions.

In preferred forms, the annular first and second surfaces are L-shapedand include first and second sections extending generallyperpendicularly to each other. The first thickness of the first sectionis perpendicular to the first thickness of the second section.

The present invention will become clearer in light of the followingdetailed description of illustrative embodiments of this inventiondescribed in connection with the drawings.

DESCRIPTION OF THE DRAWINGS

The illustrative embodiments may best be described by reference to theaccompanying drawings where:

FIG. 1 shows a plan view of a hygienic coupling and fitting seal systemaccording to the preferred teachings of the present invention.

FIG. 2 shows a cross sectional view of the seal system of FIG. 1according to section line 2-2 of FIG. 1.

FIG. 3 shows a partial, cross sectional view of the seal system of FIG.1 in use as a hygienic coupling.

FIG. 4 shows a cross sectional view illustrating use of a seal system ofFIG. 9B in a standard fitting.

FIG. 5 shows a cross sectional view illustrating use of the seal systemof FIG. 9A and the seal system of FIG. 9B in a tube or pipe coupling.

FIG. 6 shows a cross sectional view illustrating use of the seal systemof FIG. 9A in a multiple impeller shaft coupling assembly.

FIG. 7 shows a cross sectional view illustrating use of the seal systemof FIG. 9A in a removable agitator blade design.

FIG. 8 shows a cross sectional view illustrating use of the seal systemof FIG. 9B in a sanitary fitting connection between a blind threadedport or tank fitting and a screw cap fitting.

FIG. 9A-9F show cross sectional views of various embodiments of thehygienic coupling and fitting seal system according to the preferredteachings of the present invention.

FIG. 10 shows a cross sectional view illustrating use of the seal systemof FIG. 9C in a flange seal.

FIG. 11 shows a cross sectional view illustrating use of the seal systemof FIG. 9A and the seal system of FIG. 9D in an agitator bottom bearingseal in a mount.

FIG. 12 shows a cross sectional view illustrating use of the seal systemof FIG. 9D in a bolt application.

FIG. 13 shows a plan view of a further embodiment of the seal systemaccording to the preferred teachings of the present invention allowingmating with conventional seal systems.

FIG. 14 shows a cross sectional view of the seal system of FIG. 13according to section line 14-14 of FIG. 13.

FIG. 15A-15L shows further embodiments of the seal system according tothe preferred teachings of the present invention.

FIG. 16 shows a cross sectional view illustrating use of the seal systemof FIG. 9B and the seal system of FIG. 15A in an agitator bottom bearingseal in a mount.

FIG. 17 shows a cross sectional view illustrating use of the seal systemof FIG. 15K in a sanitary fitting connection between a blind threadedport or tank fitting and a screwed pipe/tube fitting.

FIG. 18 shows a cross sectional view illustrating use of the seal systemof FIG. 9A and the seal system of FIG. 15B in a stacked hub assembly foran agitator shaft with removable hub and blade assemblies and retainingnut with torque alignment pins.

All figures are drawn for ease of explanation of the basic teachings ofthe present invention only; the extensions of the figures with respectto number, position, relationship, and dimensions of the parts to formthe preferred embodiments will be explained or will be within the skillof the art after the following teachings of the present invention havebeen read and understood. Further, the exact dimensions and dimensionalproportions to conform to specific force, weight, strength, and similarrequirements will likewise be within the skill of the art after thefollowing teachings of the present invention have been read andunderstood.

Where used in the various figures of the drawings, the same numeralsdesignate the same or similar parts. Furthermore, when the terms“first”, “second”, “third”, “upper”, “lower”, “inner”, “outer”, “end”,“portion”, “section”, “axial”, “radial”, “circumferential”, “annular”,“spacing”, “length”, “thickness”, and similar terms are used herein, itshould be understood that these terms have reference only to thestructure shown in the drawings as it would appear to a person viewingthe drawings and are utilized only to facilitate describing theinvention.

DETAILED DESCRIPTION OF THE INVENTION

A hygienic coupling and fitting seal system according to the preferredteachings of the present invention is shown in the drawings andgenerally designated 10. According to the teachings of the presentinvention, seal system 10 includes a tail 14 having an annular firstsurface 16 and an annular second surface 18 which in the preferred formsshown is parallel to and spaced from annular first surface 16 in a firstdirection. Tail 14 has a first thickness T between annular first andsecond surfaces 16 and 18 in the first direction. Tail 14 furtherincludes first and second peripheral edges 22 and 28 extending betweenand adjoining annular first and second surfaces 16 and 18. First andsecond peripheral edges 22 and 28 are spaced from each other in a seconddirection perpendicular to the first direction. In the preferred formsshown, tail 14 has generally rectangular cross sections in a planeincluding the first and second directions.

According to the teachings of the present invention, a first annularring 40 integrally extends from a portion of tail 14 for a first extentE1 from first peripheral edge 22 towards but spaced from secondperipheral edge 28 of tail 14. First annular ring 40 and the portion oftail 14 form a seal 54 having an exterior including first peripheraledge 22. The exterior of seal 54 has a second thickness D parallel tofirst thickness T. Second thickness D of seal 54 continuously increasesand then continuously decreases from first peripheral edge 22 towardssecond peripheral edge 28 of tail 14. In a preferred embodiment shown inFIG. 2, seal system 10 is formed of two components 11 and 13. Component11 includes the exterior of seal 54 and a groove receiving component 13.Tail 14 is formed of component 13 and a portion of component 11 alignedwith component 13 in the second direction.

In a preferred form shown in FIGS. 2 and 9A, annular first and secondsurfaces 16 and 18 extend in a radial direction and are spaced in anaxial direction perpendicular to the radial direction. Furthermore,first peripheral edge 22 is an outer peripheral edge of tail 14, andsecond peripheral edge 28 is an inner peripheral edge of tail 14 spacedfrom the outer peripheral edge in the second direction which is theradial direction, with the inner peripheral edge radially inward of theouter peripheral edge. First annular ring 40 integrally extends fromannular first and second surfaces 16 and 18. Furthermore, in the formshown, seal 54 has generally circular cross sections in the planeincluding the first and second directions and is in the form of anO-ring 12, with first extent E1 equal to the maximum second thickness D.

In a preferred form shown in FIG. 9B, annular first and second surfaces16 and 18 extend in a radial direction and are spaced in an axialdirection perpendicular to the radial direction. Furthermore, firstperipheral edge 22 is the inner peripheral edge of tail 14, and secondperipheral edge 28 is the outer peripheral edge of tail 14 spaced fromthe inner peripheral edge in the second direction which is the radialdirection, with the inner peripheral edge radially inward of the outerperipheral edge. First annular ring 40 integrally extends from annularfirst and second surfaces 16 and 18. Furthermore, in the form shown,seal 54 has generally circular cross sections in the plane including thefirst and second directions and is in the form of an O-ring 12, withfirst extent E1 equal to the maximum second thickness D.

In a preferred form shown in FIG. 9C, annular first and second surfaces16 and 18 extend in a radial direction and are spaced in an axialdirection perpendicular to the radial direction. Furthermore, firstperipheral edge 22 is the inner peripheral edge of tail 14, and secondperipheral edge 28 is the outer peripheral edge of tail 14 spaced fromthe inner peripheral edge in the second direction which is the radialdirection, with the inner peripheral edge radially inward of the outerperipheral edge. First annular ring 40 integrally extends from annularfirst surface 16, and the exterior of seal 54 includes annular secondsurface 18 for first extent E1 from first peripheral edge 22 of tail 14towards but spaced from second peripheral edge 28 of tail 14.Furthermore, in the form shown, seal 54 has generally semicircular crosssections 58 in the plane including the first and second directions.

In a preferred form shown in FIG. 9D, annular first and second surfaces16 and 18 extend in a radial direction and are spaced in an axialdirection perpendicular to the radial direction. Furthermore, firstperipheral edge 22 is the outer peripheral edge of tail 14, and secondperipheral edge 28 is the inner peripheral edge of tail 14 spaced fromthe outer peripheral edge in the second direction which is the radialdirection, with the inner peripheral edge radially inward of the outerperipheral edge. First annular ring 40 integrally extends from annularfirst surface 16, and the exterior of seal 54 includes annular secondsurface 18 for first extent E1 from first peripheral edge 22 of tail 14towards but spaced from second peripheral edge 28 of tail 14.Furthermore, in the form shown, seal 54 has generally semicircular crosssections 58 in the plane including the first and second directions.

According to further preferred forms according to the teachings of thepresent invention, a second annular ring 50 integrally extends from theother portion of tail 14 for a second extent E2 from second peripheraledge 28 towards but spaced from first peripheral edge 22. Second annularring 50 and the other portion of tail 14 form a seal element 56 havingan exterior including second peripheral edge 28. The exterior of sealelement 56 has a third thickness T3 parallel to first thickness T. Thirdthickness T3 of seal element 56 continuously increases and thencontinuously decreases from second peripheral edge 28 towards firstperipheral edge 22.

In a preferred form shown in FIG. 9E, annular first and second surfaces16 and 18 extend in a radial direction and are spaced in an axialdirection perpendicular to the radial direction. Furthermore, firstannular ring 40 integrally extends from annular first and secondsurfaces 16 and 18. Second annular ring 50 integrally extends fromannular first and second surfaces 16 and 18. Furthermore, each of seal54 and seal element 56 has generally circular cross sections in theplane including the first and second directions and in the form of anO-ring 12. Further, in the form shown, seal element 56 is of a sizesubstantially equal to seal 54, and the maximum third thickness T3 isequal to first extent E1, second extent E2, and the maximum secondthickness D and larger than first thickness T of tail 14.

In a preferred form shown in FIG. 9F, annular first and second surfaces16 and 18 extend in a radial direction and are spaced in an axialdirection perpendicular to the radial direction. Furthermore, firstannular ring 40 integrally extends from annular first surface 16, andthe exterior of seal 54 includes annular second surface 18 for firstextent E1 from first peripheral edge 22 of tail 14 towards but spacedfrom second peripheral edge 28 of tail 14. Second annular ring 50integrally extends from annular first surface 16, and the exterior ofseal element 56 includes annular second surface 18 for second extent E2from second peripheral edge 28 of tail 14 towards but spaced from firstperipheral edge 22 of tail 14. Furthermore, in the form shown, each ofseal 54 and seal element 56 has generally semicircular cross sections 58in the plane including the first and second directions. Furthermore,seal element 56 is of a size equal to seal 54, and the maximum thirdthickness T3 is equal to the maximum second thickness D which is largerthan first thickness T of tail 14.

In preferred forms shown in FIGS. 15A-15D, first annular ring 40integrally extends from annular first and second surfaces 16 and 18, andthe exterior of seal element 56 includes one of annular first and secondsurfaces 16 and 18 for second extent E2, with seal element 56 being of asize smaller than seal 54. Specifically, in the forms shown, seal 54 hasgenerally circular cross sections in the plane including the first andsecond directions, with first extent E1 of seal 54 generally more thantwo times of second extent E2 of seal element 56. Particularly, in thepreferred form shown in FIG. 15A, annular first and second surfaces 16and 18 extend in an axial direction and are spaced in a radial directionperpendicular to the axial direction. Furthermore, tail 14 is in theform of a hollow cylinder, and second annular ring 50 integrally extendsfrom annular second surface 18 that is an inner cylindrical surface ofthe hollow cylinder. Furthermore, seal 54 and seal element 56 are spacedin the second direction which is the axial direction. In the preferredform shown in FIG. 15B, annular first and second surfaces 16 and 18extend in an axial direction and are spaced in a radial directionperpendicular to the axial direction. Furthermore, tail 14 is in theform of a hollow cylinder, and second annular ring 50 integrally extendsfrom annular first surface 16 that is an outer cylindrical surface ofthe hollow cylinder. Furthermore, seal 54 and seal element 56 are spacedin the second direction which is the axial direction. In the preferredform shown in FIG. 15C, annular first and second surfaces 16 and 18extend in a radial direction and are spaced in an axial directionperpendicular to the radial direction. Furthermore, second annular ring50 integrally extends from annular first surface 16, and seal 54 andseal element 56 are spaced in the second direction which is the radialdirection, with seal 54 radially outward of seal element 56. In thepreferred form shown in FIG. 15D, annular first and second surfaces 16and 18 extend in a radial direction and are spaced in an axial directionperpendicular to the radial direction. Furthermore, second annular ring50 integrally extends from annular first surface 16, and seal 54 andseal element 56 are spaced in the second direction which is the radialdirection, with seal element 56 radially outward of seal 54.

In preferred forms shown in FIGS. 15E-15H, tail 14 is in the form of ahollow cylinder, first annular ring 40 integrally extends from annularfirst surface 16, and the exterior of seal 54 includes annular secondsurface 18 for first extent E1 from first peripheral edge 22 towards butspaced from second peripheral edge 28. Furthermore, the exterior of sealelement 56 includes one of annular first and second surfaces 16 and 18for second extent E2, with seal element 56 being of a size smaller thanseal 54. Specifically, in the forms shown, seal 54 has generallysemicircular cross sections 58 in the plane including the first andsecond directions, with first extent E1 of seal 54 generally more thantwo times of second extent E2 of seal element 56. Furthermore, annularfirst and second surfaces 16 and 18 are spaced in the first directionwhich is a radial direction, and first and second peripheral edges 22and 28 are spaced in the second direction which is an axial directionperpendicular to the radial direction. Further, seal 54 seal element 56are spaced in the second direction which is the axial direction.Particularly, in the preferred form shown in FIG. 15E, both first andsecond annular rings 40 and 50 integrally extend from annular firstsurface 16 that is an outer cylindrical surface of the hollow cylinder.In the preferred form shown in FIG. 15F, first annular ring 40integrally extend from annular first surface 16 that is an innercylindrical surface of the hollow cylinder, and second annular ring 50integrally extends from annular second surface 18 that is the outercylindrical surface of the hollow cylinder. In the preferred form shownin FIG. 15G, both first and second annular rings 40 and 50 integrallyextend from annular first surface 16 that is the inner cylindricalsurface of the hollow cylinder. In the preferred form shown in FIG. 15H,first annular ring 40 integrally extends from annular first surface 16that is the outer cylindrical surface of the hollow cylinder, and secondannular ring 50 integrally extends from annular second surface 18 thatis the inner cylindrical surface of the hollow cylinder.

In preferred forms shown in FIGS. 15I-15L, tail 14 is L-shaped.Specifically, annular first and second surfaces 16 and 18 are L-shapedand include first and second sections 62 and 64 extending generallyperpendicular to each other. First thickness T of first section 62 isperpendicular to first thickness T of second section 64. Furthermore,second section 64 is in the form of a hollow cylinder, and first section62 is in the form of a radially extending flange. First annular ring 40integrally extends from annular first surface 16, and the exterior ofseal 54 includes annular second surface 18 for first extent E1 fromfirst peripheral edge 22 towards but spaced from second peripheral edge28. Furthermore, the exterior of seal element 56 includes one of annularfirst and second surfaces 16 and 18 for second extent E2, with sealelement 56 being of a size smaller than seal 54. Specifically, in theforms shown, seal 54 has generally semicircular cross sections 58 in theplane including the first and second directions, with first extent E1 ofseal 54 generally more than two times of second extent E2 of sealelement 56.

Particularly, in the preferred form shown in FIG. 151, first annularring 40 integrally extends from annular first surface 16 of firstsection 62 extending radially outwardly of second section 64, withannular first surface 16 of second section 64 being a radially outersurface of the hollow cylinder forming second section 64. Furthermore,second annular ring 50 integrally extends from annular first surface 16of second section 64. In the preferred form shown in FIG. 15J, firstannular ring 40 integrally extends from annular first surface 16 offirst section 62 extending radially outwardly of second section 64, withannular first surface 16 of second section 64 being a radially innersurface of the hollow cylinder forming second section 64. Furthermore,second annular ring 50 integrally extends from annular second surface 18of second section 64. In the preferred form shown in FIG. 15K, firstannular ring 40 integrally extends from annular first surface 16 offirst section 62 extending radially inward of second section 64, withannular first surface 16 of second section 64 being the radially innersurface of the hollow cylinder forming second section 64. Furthermore,second annular ring 50 integrally extends from annular first surface 16of second section 64. In the preferred form shown in FIG. 15L, firstannular ring 40 integrally extends from annular first surface 16 offirst section 62 extending radially inward of second section 64, withannular first surface 16 of second section 64 being a radially outersurface of the hollow cylinder forming second section 64. Furthermore,second annular ring 50 integrally extends from annular second surface 18of second section 64.

According to the teachings of the present invention, seal system 10 isformed from sealable/compression control type materials and in the mostpreferred form is Telfon based. However, other thermoplastics (TP) orthermoplastic elastomers (TPEs) type materials can be used.

In a preferred form shown in FIGS. 13 and 14, annular first and secondsurfaces 16 and 18 extend radially. Seal system 10 includes seal 54 inthe most preferred form shown as a half O-ring 102 formed on annularfirst surface 16 of tail 14, seal element 56 in the most preferred formshown as a half O-ring 104 formed on annular second surface 18 of tail14, and a tail extension 106. Seal 54 and seal element 56 are radiallyspaced from and oppose each other, with seal element 56 located radiallyoutward of seal 54. Seal element 56 includes an annular groove 23 insecond peripheral edge 28, and tail extension 106 includes a ledge 108engaged in annular groove 23. Tail extension 106 may be separatelyformed and in the most preferred form of different materials than tail14, seal 54, and seal element 56 such as of non-compressible material.Seal 54 is of a larger radius than seal element 56, with seal 54 havinga radius of 0.70 inches (1.78 cm) and with seal element 56 having aradius of 0.46 inches (1.17 cm) in the most preferred form shown. Sealsystem 10 is advantageous in that one side of it can adopt aconventional seal installation. As an example, seal system 10 can matewith current industry seal systems. Other similar adaptations toexisting seals can be made according to the teachings of the presentinvention.

Now that the basic construction of the seal systems 10 of the preferredteachings of the present invention has been explained, the operation andsome of the advantages of seal systems 10 can be set forth andappreciated. In an application of seal systems 10 of FIGS. 1, 2, 9A, and9B between first and second fitting members 70 and 80 shown in FIG. 3,seal system 10 is generally mounted between an end face 72 of firstfitting member 70 and an end face 82 of second fitting member 80 to forma sealing assembly. First and second fitting members 70 and 80 aremounted in an environment containing and/or allowing passage of aproduct such as a fluid and extend in the first direction. First andsecond fitting members 70 and 80 include a product contact side 86 incontact with the product. End face 72 of first fitting member 70 extendsin the second direction and includes an annular groove 20 adjoiningproduct contact side 86. Annular groove 20 is of a size equal to aportion of first annular ring 40 extending from annular first surface 16away from annular second surface 18. In the preferred forms shown, endface 82 of second fitting member 80 extends in the second direction andincludes an annular groove 21 facing annular groove 20. Annular groove21 has a size equal to another portion of first annular ring 40extending from annular second surface 18 away from annular first surface16. Annular groove 20 has a diameter which is the same as that ofannular groove 21. An annular gap 74 is defined between end faces 72 and82 and in communication with annular grooves 20 and 21. Annular gap 74has a depth D1 in the first direction equal to first thickness T of tail14. Seal 54 in the form of O-ring 12 is received in annular grooves 20and 21 and adjacent product contact side 86, and tail 14 is received inannular gap 74. Thus, seal 54 is exposed on product contact side 86between end faces 72 and 82 generally equal to depth D1.

Seal systems 10 according to the preferred teachings of the presentinvention can have various applications and can be utilized in variouscombinations. FIG. 4 shows use of seal system 10 of FIG. 9B betweenfirst and second fitting members 70 and 80 in the preferred form shownas two pipes, with product contact side 86 inside of the two pipes. FIG.5 shows use of a combination of seal system 10 of FIG. 9A and sealsystem 10 of FIG. 9B in a tube or pipe coupling of a conduit includingfirst and second fitting members 70 and 80. The conduit passes through atank or the like containing fluid, with the fluid on inside and outsideof the conduit. FIG. 6 shows use of seal system 10 of FIG. 9A in amultiple impeller shaft coupling assembly including a plurality ofshafts 94 for operation in fluid, such shafts 94 including blades foragitating the fluid located outside of shafts 94. FIG. 7 shows use ofseal system 10 of FIG. 9A in a removable agitator blade design betweenan impeller blade 90 and a connection element 92. FIG. 8 shows use ofseal system 10 of FIG. 9A in a sanitary fitting connection between firstfitting member 70 in the preferred form shown as a blinded threaded portor tank fitting 24 and second fitting member 80 in the preferred formshown as a screw cap fitting 26. FIG. 10 shows use of seal system 10 ofFIG. 9C in a flange seal between first and second fitting members 70 and80. FIG. 11 shows use of seal system 10 of FIG. 9A and seal system 10 ofFIG. 9D in an agitator bottom bearing seal in a mount 30 including firstand second fitting members 70 and 80. FIG. 12 shows use of seal system10 of FIG. 9D in a bolt application. An optional agitator coupling‘stop’ bolt utilizing seal system 10 of the present invention guaranteesno backing out during operation. This bolt seal design can also be usedfor other bolting applications having product contact such as pumpimpeller retaining bolts.

Likewise, FIG. 16 shows use of a combination of seal system 10 of FIG.9B and the seal system of FIG. 15A in an agitator bottom bearing seal ina mount 30 including first and second fitting members 70 and 80. Forseal system 10 of FIG. 15A, first fitting member 70 includes an annularrecess 84 extending perpendicularly to and in communication with annulargap 74. Annular recess 84 has a spacing to product contact side 86larger than annular groove 20. In this application, seal element 56having a size smaller than seal 54 acts as a retaining lip, and sealsystem 10 with seal element 56 is compressed by the ID/OD fit of mount30, unlike the normal compression method. Specific tolerances areapplied for the correct compression. In its most preferred form ofTeflon or thermoplastic, installation while screwing or rotating is easydue to the self-lubricating seal system 10 and non-binding of seal 54 inthe form of O-ring 12. In this application, the seal is static but issealed in the rotational direction.

Furthermore, FIG. 17 shows use of seal system 10 of FIG. 15K in asanitary fitting connection between first fitting member 70 in thepreferred form shown as a blind threaded port or tank fitting 32 andsecond fitting member 80 in the preferred form shown as a screwedpipe/tube fitting 33. It can be appreciated that first fitting member 70includes an L-shaped annular gap 74 including first and second portionsextending generally perpendicularly to each other. Furthermore, firstfitting member 70 includes an annular recess 84 extendingperpendicularly to and in communication with the second portion ofannular gap 74. Annular recess 84 has a spacing to product contact side86 larger than annular groove 20. L-shaped tail 14 is received inL-shaped annular gap 74, and seal element 56 of a size smaller than seal54 and acting as a retaining lip is received in annular recess 84.

Further, FIG. 18 shows use of a combination of seal system 10 of FIG. 9Aand seal system 10 of FIG. 15B in a stacked hub assembly for an agitatorshaft 38 with removable impeller blade and hub assemblies 34 and 35 anda retaining nut 36 with torque alignment pins 37. This applicationallows agitator impeller blade and hub assemblies 34 and 35 to beinstalled and removed on agitator shaft 38 while maintaining hygienicsealing effect. Similar to FIG. 16, seal system 10 with seal element 56of a size smaller than seal 54 and acting as a retaining lip iscompressed by the ID/OD fit of retaining nut 36 and agitator shaft 38 inFIG. 18. Unlike the normal compression method, in addition an angle A,ranging from 0-3 degrees, preferable 1 degree, produces a taper to allowa loose fit during initial assembly but ensures the correct compressionwhen assembled completely. Specific tolerances are applied for thecorrect compression. This angle and compression method can also beapplied to FIG. 16 according to the teachings of the present invention.

Seal systems 10 according to the preferred teachings of the presentinvention allow a flush seal surface and cleanability in product contactside 86. Specifically, conventional flat gaskets can ‘extrude’ or create‘overhang’ which creates cleaning problems. In the application of sealsystem 10 having seal 54 in the form of O-ring 12 utilized in first andsecond fitting members 70 and 80 having annular grooves 20 and 21, seal54 is free of protrusions and exposed on product contact side 86 througha gap between end faces 72 and 82 generally equal to depth D1. Thus,tail 14 and dual side annular grooves 20 and 21 of the seal systemaccording to the teachings of the present invention allow seal 54 to becompressed without being “extruded” and allow easy installation. Seal 54is allowed to be “pushed out flush” into product contact areas, so that“flat” areas on the product contact side in conventional O-rings thatcan be more difficult to clean is eliminated in seal systems 10according to the preferred teachings of the present invention. Smoothprofile on the inner or outer diameter of seal 54 and annular grooves 20and 21 eliminate gasket ‘extrusion’ and allows better cleanability.However, seal 54 can be compressed to a designated amount, such as butnot limited to 0.020 inches (0.05 cm) in the preferred form, soextrusion is limited and remains smooth/round. It can be appreciatedthat dual sided annular grooves 20 and 21 allow even compression on bothsides, which is advantageous over conventional O-ring methods usuallyemploying one-sided machining only. When utilized in agitator couplings,seal 54 remains engaged, unlike conventional O-rings that remain engagedbut normally have crevices that can be more difficult to clean.

Seal systems 10 according to the teachings of the present inventionincluding seal 54 and seal element 56 in the form of O-ring 12 and/orsemicircular cross sections also provide better cleanability in productcontact side 86, because seal 54 and seal element 56 are free ofprotrusions and are exposed on product contact side 86. Furthermore,seal 54 and seal element 56 have smooth profiles and do not protrudeinto product contact side 86 so that are no flat areas.

Furthermore, conventional O-ring methods usually require holding agasket in place until almost tight. Seal systems 10 according to thepreferred teachings of the present invention are self-centering for easeof installation. Furthermore, seal element 56 of a size smaller thanseal 54 and acting as a retaining lip can hold seal system 10 to allowinstallation without holding seal systems 10 in place, eliminating thepossibility of pinching fingers. Specifically, seal element 56 acting asa retaining lip helps retain seal system 10 during assembly. Sealelement 56 acting as a retaining lip is designed to allow easy assembly,especially in blind applications as shown in FIG. 17.

Furthermore, seal systems 10 according to the preferred teachings of thepresent invention can be tightened/secured without the ‘binding andrippling up’ which commonly occurs on conventional flat gaskets,O-rings, and other industry standard gaskets and which creates potentialfor loosing the sealing effect and becomes a cleaning issue. Due toself-lubricating in its most preferred form of Teflon or thermoplastic,seal systems 10 of the present invention allow circumferential directionwhile achieving a tight compressive sealing effect.

Now that the basic teachings of the present invention have beenexplained, many extensions and variations will be obvious to one havingordinary skill in the art. For example, although seal 54 and sealelement 56 are shown as being of circular or semicircular crosssections, seal 54 and seal element 56 can have other shapes according tothe preferred teachings of the present invention including ellipsoidal,race tank shaped, or the like. Further, seal systems 10 according to thepreferred teachings of the present invention can be utilized incombination other than those shown.

Thus since the invention disclosed herein may be embodied in otherspecific forms without departing from the spirit or generalcharacteristics thereof, some of which forms have been indicated, theembodiments described herein are to be considered in all respectsillustrative and not restrictive. The scope of the invention is to beindicated by the appended claims, rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are intended to be embraced therein.

1. A seal system comprising: a tail including an annular first surfaceand an annular second surface parallel to and spaced from the annularfirst surface in a first direction, with the tail having a firstthickness between the annular first and second surfaces in the firstdirection, with the tail further including first and second peripheraledges extending between and adjoining the annular first and secondsurfaces, with the first and second peripheral edges spaced from eachother in a second direction perpendicular to the first direction; and afirst annular ring integrally extending from a portion of the tail for afirst extent from the first peripheral edge towards but spaced from thesecond peripheral edge of the tail, with the first annular ring and theportion of the tail forming a seal, with the seal including an exteriorincluding the first peripheral edge, with the exterior of the sealhaving a second thickness parallel to the first thickness, with thesecond thickness of the seal continuously increasing and thencontinuously decreasing from the first peripheral edge towards thesecond peripheral edge of the tail, and with the exterior of the sealfree of protrusions.
 2. The seal system as claimed in claim 1, with thefirst annular ring integrally extending from the annular first surface,and with the exterior of the seal including the annular second surfacefor the first extent from the first peripheral edge towards but spacedfrom the second peripheral edge.
 3. The seal system as claimed in claim2, with the seal having generally semicircular cross sections in a planeincluding the first and second directions.
 4. The seal system as claimedin claim 1, with the first annular ring integrally extending from theannular first and second surfaces.
 5. The seal system as claimed inclaim 4, with the seal having generally circular cross sections in aplane including the first and second directions.
 6. The seal system asclaimed in claim 1, further comprising: a second annular ring integrallyextending from another portion of the tail for a second extent from thesecond peripheral edge towards but spaced from the first peripheraledge, with the second annular ring and the other portion of the tailforming a seal element, with the seal element including an exteriorincluding the second peripheral edge, with the exterior of the sealelement having a third thickness parallel to the first thickness, withthe third thickness of the seal element continuously increasing and thencontinuously decreasing from the second peripheral edge towards thefirst peripheral edge, and with the exterior of the seal element free ofprotrusions.
 7. The seal system as claimed in claim 6, with the secondannular ring integrally extending from one of the annular first andsecond surfaces, and with the exterior of the seal element includinganother of the annular first and second surfaces for the second extentfrom the second peripheral edge towards but spaced from the firstperipheral edge.
 8. The seal system as claimed in claim 6, with the sealelement being of a size substantially equal to the seal.
 9. The sealsystem as claimed in claim 6, with the seal element being of a sizesmaller than the seal.
 10. The seal system as claimed in claim 6, withthe first annular ring integrally extending from the annular firstsurface, and with the second annular ring integrally extending from theannular second surface.
 11. The seal system as claimed in claim 10, withthe first annular ring integrally extending from the annular first andsecond surfaces.
 12. The seal system as claimed in claim 6, with theannular first and second surfaces being L-shaped and including first andsecond sections extending generally perpendicularly to each other, andwith the first thickness of the first section being perpendicular to thefirst thickness of the second section.
 13. The seal system as claimed inclaim 12, with the first annular ring integrally extending from theannular first surface, and with the exterior of the seal including theannular second surface for the first extent from the first peripheraledge towards but spaced from the second peripheral edge, with the secondannular ring integrally extending from one of the annular first andsecond surfaces, and with the exterior of the seal element includinganother of the annular first and second surfaces for the second extentfrom the second peripheral edge towards but spaced from the firstperipheral edge.
 14. A seal assembly comprising: a first fitting memberextending in a first direction and having a first end face extending ina second direction perpendicular to the first direction, with the firstend face including an annular first groove; a second fitting memberincluding a second end face coupled to the first end face with anannular gap defined between the first and second end faces and incommunication with the annular first groove, with the annular gap havinga depth in the first direction, with the first and second fittingmembers adapted to be mounted in an environment containing a fluid, withthe first and second fitting members including a side in contact withthe fluid, with the annular gap having a spacing in the second directionto the side larger than the annular first groove of the first fittingmember, with the first annular groove adjoining the side; and a sealsystem mounted between the first and second end faces, with the sealsystem including a tail having an annular first surface and an annularsecond surface parallel to and spaced from the annular first surface inthe first direction, with the tail received in the annular gap andhaving a first thickness between the annular first and second surfacesin the first direction equal to the depth of the annular gap, with thetail further including first and second peripheral edges extendingbetween and adjoining the annular first and second surfaces, with thefirst and second peripheral edges spaced from each other in the seconddirection, with the seal system further including a first annular ringintegrally extending from a portion of the tail for an extent from thefirst peripheral edge towards but spaced from the second peripheral edgeof the tail, with the first annular ring and the portion of the tailforming a seal, with the seal including an exterior including the firstperipheral edge, with the exterior of the seal having a second thicknessparallel to the first thickness, with the second thickness of the sealcontinuously increasing and then continuously decreasing from the firstperipheral edge towards the second peripheral edge of tail, with thefirst annular ring received in the annular first groove, and with theexterior of the seal system free of protrusions.
 15. The seal assemblyas claimed in claim 14, with the second end face of the second fittingmember including an annular second groove facing and aligned with theannular first groove, with the first annular ring of the seal integrallyextending from the annular first and second surfaces, and with the sealhaving generally circular cross sections and received in the annularfirst and second grooves.
 16. The seal assembly as claimed in claim 14,with the first annular ring integrally extending from the annular firstsurface, and with the exterior of the seal including the annular secondsurface for the extent from the first peripheral edge towards but spacedfrom the second peripheral edge.
 17. The seal assembly as claimed inclaim 16, with the seal having generally semicircular cross sections ina plane including the first and second directions.
 18. The seal assemblyas claimed in claim 14, with the first fitting member further includingan annular recess extending perpendicularly to and in communication withthe annular gap, with the annular recess having a spacing to the sidelarger than the first annular groove, with the seal assembly furthercomprising: a second annular ring integrally extending from anotherportion of the tail from the second peripheral edge towards but spacedfrom the first peripheral edge, with the second annular ring and theother portion of the tail forming a seal element, with the seal elementincluding an exterior including the second peripheral edge, with theexterior of the seal element having a third thickness parallel to thefirst thickness, with the third thickness of the seal elementcontinuously increasing and then continuously decreasing from the secondperipheral edge towards the first peripheral edge, and with the exteriorof the seal element free of protrusions, and with the second annularring received in the annular recess.
 19. The seal assembly as claimed inclaim 18, with the annular gap being L-shaped and including first andsecond portions extending generally perpendicularly to each other, withthe annular first and second surfaces being L-shaped and including firstand second sections extending generally perpendicularly to each otherand received in the first and second portions of the annular gap, andwith the first thickness of the first section being perpendicular to thefirst thickness of the second section.
 20. The seal assembly as claimedin claim 19, with the seal element being of a size smaller than theseal, with the first annular ring integrally extending from the firstannular surface of the first section, and with the second annular ringintegrally extending from one of the annular first and second surfacesof the second section.